This invention relates to containers made of corrugated paperboard, and more particularly to a container which is easily formed from a blank and has a locking bottom.
Paperboard cartons come in a wide variety of structures to enable them to carry heavy loads. To facilitate shipping, the containers are formed from blanks which are then formed into containers on site. Prior art blanks had a solid bottom These blanks, however, are costly and the industry is switching to blanks having side and end walls and a locking bottom formed from flaps which are hingedly connected to the side and end walls.
Booth U.S. Pat. No. 4,821,949 discloses a container blank for forming a container wherein flap locking slits are formed at the ends of a major flap. U.S. Pat. No. 4,650,112 shows earlier technology. The locking slits of Booth include a first portion and a second portion which together define a flap retaining segment and an angular slit extending angularly from the end of the second portion to provide flexibility to the flap retaining segment. Although the angular slit may provide flexibility to the flap retaining segment, it does not aid in the insertion of the flap into the flap retaining segment such as by opening the flap retaining segment. Also, the patent to Peeples U.S. Pat. No. 4,279,377, shows early related structure.